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multicore processor speeds

A friend and I have been in disagreement over the following question for the past couple of weeks, and I'm hoping someone here could give me some references to send to him. He agrues that the speed listed on multicore CPU's is the speed of all of the cores added together. I, on the other hand, insist that it is the speed of each individual core. Anyone able to help me put an end to this debate?

ok.. speaking from sheer hearsay... I would agree with you... if you have a pentium core 2 duo running at 1.8Ghz, you should have the equiv of 2 1.8ghz processors running. I am sure that if I am wrong, someone will correct me promptly, which is actually appreciated. I would rather swallow my pride and learn something new, than continue with flawed knowledge...

\"Those of us that had been up all night were in no mood for coffee and donuts, we wanted strong drink.\"

The frequency is given on a per core-basis (often that number is even
referred to as the 'core frequency')

reason

It is all about performance, energy-efficiency and temperature.

In [1, p.3] there is a graph that shows power consumption in dependency
of the performance via over/under-clocking. You can see that a slight
boost of performance increases the power-consumption heavily,
a slight decrease of performance decreases the power-comsumption heavily.

Thus, plot below, two slightly 'under-clocked' cores uses the same power
as one single-core at maximum frequency (not overclocked!) but results in
73% percent more performance.

Would this be dependent on the manufacturer of the processor or the architecture of the processor?

I mean with Intel (as a hypothetical example, I don't know honestly if this is true or not) suppose they counted the frequency on each core...does that mean that the ARM11 MPCore processor would follow the same protocol?

I honestly don't know but I'm willing to blindly guess the answer is "yes"...correct me if I am wrong (which I probably am...).

"The Texan turned out to be good-natured, generous and likeable. In three days no one could stand him." Catch 22 by Joseph Heller.

It is indeed the speed of each core separate. Lets use the infamous Xbox 360 as an example/reference, it uses a special multi-core processor with three cores, each having 3.2 GHz a piece. Giving it (when push comes to shove) a max of 9.6 GHz... BUT it doesn't ever use these for one specific purpose, game designers split these cores up giving certain jobs for each core; such as shadow rendering to one core etc...

now if it was the way your friend said it is, they would play out like this... 3 cores with 1.06 GHz a piece. this just wouldn't cut it...

Multi-core processors were an advance in technology, if it was the way your friend says it is, we would just be competing with the latest single core processors... these links will help sway your friend.

No the speeds are not to be added together to get one large one, it doesnt work that way.

Not sure about the xbox game developers but with pc's the OS handles the scheduling of processes on the cores.

If you would like to know the exact details of how multicore processors works, I can recommend a book that is very boring but explains it all. I had to read the book for my advanced computer architecture class. Part of the graduate curriculum at my uni.
Computer Architecture: A quantitative approach fourth edition

<chsh> I've read more interesting technical discussion on the wall of a public bathroom than I have at AO at times